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Plotting Strangeness? - Printable Version

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Plotting Strangeness? - oldhpfan - 09-20-2014 11:37 PM

I was playing around plotting equations in the advanced graphing app to get fun shapes.
These two equations, and variants, produce some weird behavior when plotting, it's like the calculator (and emulator, though faster) are plotting a bunch of extra points then eliminating them to get the correct line in parts of the plot.
X=Y^3 -5*Y^2 + 15
X=Y^4 -5*Y^2 + 15 (looks like a sigma)
Really slows down the plot. Any ideas what is going on? I have not noticed this yet when plotting functions and other non functions like X^2+y^2 are fine.


RE: Plotting Strangeness? - Han - 09-21-2014 01:49 PM

That's just how the advanced grapher works -- by design. It uses adaptive techniques to refine the graph until further refinements are no longer visible within the current window settings.


RE: Plotting Strangeness? - oldhpfan - 09-22-2014 05:25 AM

I figured it might be, looks strange the first time you run across it though especially with simple equations like I'm playing with. Thanks.


RE: Plotting Strangeness? - ColinJDenman - 09-23-2014 08:37 PM

(09-22-2014 05:25 AM)oldhpfan Wrote:  I figured it might be, looks strange the first time you run across it though especially with simple equations like I'm playing with. Thanks.

You might change the method of plotting in the plot setup page, the other 2 methods can yield slightly different plots.